Dramatic advances are being made in the techniques available for isolation and structural studies of natural products. This has made it feasible to investigate the structures, mode of action, receptor sites, membrane transport, etc. of compounds which exist in minute quantities but which nevertheless exert pronounced effects on animal and plant life. Many such problems lie in the borderline area between the various scientific disciplines. The approach is to select challenging problems in the biosciences and elucidate them on a chemical structural base, collaborating with scientists in other fields, whenever necessary. The projects to be studied include insect growth regulators, crustacean hormone, marine respiratory pigments, marine neurotoxins, etc.